From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-11.2 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_CR_TRAILER,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 63787C433DB for ; Wed, 20 Jan 2021 14:23:25 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 33CCA23329 for ; Wed, 20 Jan 2021 14:23:25 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726468AbhATOWz (ORCPT ); Wed, 20 Jan 2021 09:22:55 -0500 Received: from mail.kernel.org ([198.145.29.99]:38512 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2390289AbhATOWf (ORCPT ); Wed, 20 Jan 2021 09:22:35 -0500 Received: by mail.kernel.org (Postfix) with ESMTPSA id E2D7F23329; Wed, 20 Jan 2021 14:21:52 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1611152514; bh=ZkozHMUf9stDUHKmkmTqqNuOaUV2CAaauHyw34bpx48=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=e/+tZ5ML2YRbpnqwJCZ3J6qdvWT002Zjr+66oDAPFpC388jQqDKiemBdBsAKckpm8 p9Ay084F4wq6CybP/avG+icvUin+D8doSLhiUmeIsBjZ3b+FmWYGW9FVl38IsHZZnb PSZw2wz9abn7jecNI5vVxpga4gbVt/yZroLz8kZ48NJzmDfpZ3bKmbysR/r73xcfqS hKcQCQVIQj1EEhebz6C5dmDGbq0VfTE3YF4Q4RbZSWSnDHvQOptDKfDeJO6pC+fLCW EgSE4KMyUYGFyAmf5zW727nNmyTst2zihekXMYQtHQ+g+UVGeC6XQKoHfB5f7Ev/Pd mNCAIsAdDWzSg== Date: Wed, 20 Jan 2021 16:21:49 +0200 From: Jarkko Sakkinen To: Elaine Palmer Cc: Sumit Garg , Mimi Zohar , linux-integrity@vger.kernel.org, Elaine Palmer , George Wilson , zgu@us.ibm.com Subject: Re: [PATCH] doc: trusted-encrypted: updates with TEE as a new trust source (update) Message-ID: References: <20201209164249.715178-1-zohar@linux.ibm.com> <20201211081454.GA5262@kernel.org> <19d3547b-c285-aa98-0cc3-cc55ef09a1b9@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <19d3547b-c285-aa98-0cc3-cc55ef09a1b9@gmail.com> Precedence: bulk List-ID: X-Mailing-List: linux-integrity@vger.kernel.org On Fri, Jan 15, 2021 at 06:15:51PM -0500, Elaine Palmer wrote: > > > On 1/13/21 4:23 PM, Jarkko Sakkinen wrote: > > On Tue, Jan 12, 2021 at 10:55:44AM +0530, Sumit Garg wrote: > > > On Sun, 10 Jan 2021 at 08:46, Jarkko Sakkinen wrote: > > > > On Mon, Jan 04, 2021 at 06:06:33PM +0530, Sumit Garg wrote: > > > > > Hi Jarkko, On Fri, 11 Dec 2020 at 13:44, Jarkko Sakkinen > > > > > wrote: > > > > > > On Wed, Dec 09, 2020 at 11:42:49AM -0500, Mimi Zohar wrote: > > > > > > > From: Elaine Palmer Update > > > > > > > trusted key documentation with additional > > > > > > > comparisons between discrete TPMs and TEE. > > > > > > > Signed-off-by: Elaine Palmer > > > > > > Right, so OP-TEE is not the same as TEE. I did not know > > > > > > this and the patch set does not underline this. I > > > > > > re-checked the patches and none of them say explicitly > > > > > > that OP-TEE is an application living inside TEE. > > > > > This patch-set provides a trust source based on generic TEE > > > > > interface where underlying TEE implementations like OP-TEE > > > > > (drivers/tee/optee/), AMD TEE (drivers/tee/amdtee/) etc. can > > > > > easily be hooked up. And this is similar to the TPM > > > > > interface where underlying TPM implementations like discrete > > > > > TPM, virtual TPM, firmware TPM etc. can be easily hooked up. > > > > > > This essentially means that the backend needs to be > > > > > > renamed as "op_tee". > > > > > I don't see any need for this, see above. > > > > Right, TEE is a protocol standard, just like TPM, and OP-TEE is > > > > one implementation of this interface? I.e. OP-TEE does not > > > > define API that is hard bound to OP-TEE? > > > Yes, OP-TEE doesn't define a hard bound client interface API. The > > > client API is based on TEE client API specification [1] from > > > GlobalPlatform. [1] > > > http://globalplatform.org/specs-library/tee-client-api-specification/ > > > -Sumit > > Thanks, bookmarked. No need for name change. /Jarkko > This discussion has illustrated that even those of us who live and > breathe this stuff could use clarification.  Shouldn't we recommend > that the Trust Source have a hardware root of trust?  We could be > even more specific.  For example, the documentation could recommend > that a TPM be evaluated under "TCG Protection Profile for PC Client > Specific TPM 2.0" or later and a TEE be evaluated under GlobalPlatform > "TEE Protection Profile v1.3, GPD_SPE_021" or later.  Of course, our > recommendation would not be a requirement, but it would provide > guidance for deployment as well as precedent for future Trust Sources. Recommend what? Not following. I don't undestand what recommending trust sources means, and why it's written as Trust Sources. /Jarkko > I know where I'm getting stuck is on TEEs as a concept vs > TEEs with specific hardware requirements and interfaces. > The same applies to TPMs.  There are hardware TPMs that meet > the protection profile and there are other implementations > (e.g., vTPMs) that use the same interface, but aren't anchored in > hardware. > > I know if I were deploying a server, mobile device, or IoT device, I'd > want to know exactly what is protecting my keys.  A generic TPM or TEE > doesn't tell me enough. > > -Elaine > > >